IP Library › Granted Patent US 6,683,709
Granted Patent Utility
US 6,683,709 · App. 10/067,529

Photochromic pyran compounds

Inventors: Claudia Mann, Udo Weigand, Manfred Melzig
Patented Case View Patent ↗
Granted: Jan 27, 2004 Filed: Feb 7, 2002
Inventors
Claudia Mann
Udo Weigand
Manfred Melzig
Assignee (at issue)
RODENSTOCK GMBH

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Quick Facts
Patent No.
US 6,683,709
App. No.
10/067,529
Filed
2002-02-07
Granted
2004-01-27
Kind
B2